Manufacturing method of a weight parts integratedly connected with a forged golf club head

ABSTRACT

A method of forming a weight part integratedly connected with a forged golf club head includes steps of a club head forming step, at least one engaging recess forming step, at least one weight part engaging step, and a step of integratedly connecting the at least one weight part with the club head by forging. A crude rod is provided into a raw forging die and formed to a club head by a forging process. At least one engaging recess is formed in a sole portion or a back portion of the club head by a machining method. At least one weight part is engaged into the at least one engaging recess of the club head. The club head with the at least one weight part is pressed by a forging process to make the material of the club head cover the at least one weight part completely without gaps.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a manufacturing method of a golf club head, especially to a manufacturing method of a weight parts integratedly connected with a forged golf club head.

2. Description of Related Art

A conventional iron golf club has a club head and a weight part mounted in the club head, mostly mounted in a sole portion or a back portion of the club head. The weight part usually has a higher specific gravity than the club head such that the iron golf club head has balanced weight distribution to improve striking performances or to increase the striking distance. Normally, material having a high specific gravity (10˜18 g/c.c) such as WC (Tungsten Alloy) is selected for the weight part.

The conventional manners for connecting the weight part and the iron golf club are as follows:

1. Screw connection:

At least one tungsten alloy screw is screwed into a body of the iron golf club head to distribute the weight of the iron golf club head. However, the screw connection is not firm and the tungsten alloy screw may easily loosen or fall off, and causes a sound of vibration in striking.

2. Welding connection of different materials:

By welding a tungsten alloy weight with the club head of the iron golf club that is made of carbon steel or stainless steel, two materials of different specific gravities are connected to each other to achieve a better weight distribution. However, since the materials of the weight part and the club head are different, the weight part easily splits or falls off from the club head in striking.

3. Engagement connection:

By pressing or pushing the weight into a recess of the club head of the iron golf club, the weight part is connected with the club head but a gap is existed between the weight and the club head. The weight part and the club head are not integrally connected to each other, such that the weight easily falls off or causes a sound of vibration in striking.

To overcome the shortcomings of the conventional manufacturing methods, the present invention provides a manufacturing method of a weight parts integratedly connected with a forged golf club head to mitigate or obviate the aforementioned problems.

SUMMARY OF THE INVENTION

The main objective of the present invention is to provide a method of forming a weight part integratedly connected with a forged golf club head, including steps of forming a club head forming step, at least one engaging recess forming step, at least one weight parts engaging step, and a step of integratedly connecting the at least one weight part with the club head by forging. A crude rod is provided into a raw forging die and formed to a club head by a forging process. At least one engaging recess is formed in a sole portion or a back portion of the club head by a machining method. At least one weight part is provided and is engaged into the at least one engaging recess of the club head. The club head with the at least one weight part is pressed by a forging process to make the material of the club head cover the weight parts completely without any gaps.

Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a manufacturing method of a weight parts integratedly connected with a forged golf club head in accordance with the present invention;

FIG. 2 is an operational perspective view of the golf club head manufactured by the method in FIG. 1, showing a crude rod is provided to form a club head;

FIG. 3 shows operational perspective views of the golf club head manufactured by the method in FIG. 1, showing an engaging recess is formed on a sole portion of the club head;

FIG. 4 shows operational perspective views of the golf club head manufactured by the method in FIG. 1, showing a weight parts engaged into the engaging recess;

FIG. 5 is an operational perspective view of the golf club head manufactured by the method in FIG. 1, showing the club head with the engaged weight parts in a forging process;

FIG. 6 is a perspective view of the golf club head manufactured by the method in FIG. 1, showing a completed iron golf club head;

FIG. 7 shows operational perspective views of a second embodiment of the golf club head manufactured by the method in FIG. 1, showing an engaging recess is formed on a back portion of the club head and the weight parts engaged into the engaging recess.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

With reference to FIG. 1, a manufacturing method of a weight parts integratedly connected with a forged golf club head in accordance with the present invention comprises the following steps: a club head forming step S1, at least one engaging recess forming step S2, at least one weight part engaging step S3, and a step of integratedly connecting the weight parts with the club head by forging S4.

With reference to FIGS. 1 and 2, in the step S1 of forming a club head by forging, a crude rod 10 is put in a raw forging die 20 and formed into a club head 30 by a forging process.

The crude rod 10 has a predetermined diameter and length based on the predetermined size of a golf club head. The crude rod 10 is made of metal such as carbon steel, stainless steel or the like. According to carbon content or the alloy elements of the material, the carbon steel for the crude rod 10 may be selected from 1020C,1025C,1035C,1045C,35CrMo,42CrMo etc; the stainless steel for the crude rod 10 may be selected from SUS303, SUS304,SUS431,17-4,etc.

Additionally, the forging process of forming the club head 30 may be a single forging process or a multi-forging process. The single step forging comprises a rough forging process to form the crude rod 10 as the club head 30. The multi-forging process comprises a rough forging process and a fine forging process to form the crude rod 10 as the club head 30, or comprises a rough forging process, a fine forging process, and a final forging process to form the crude rod 10 as the club head 30. The multi-forging process can obtain a club head 30 having a precise weight, specifications and appearance. Preferably, the crude rod 10 is made of carbon steel and the forging process is a multi-forging process.

With reference to FIGS. 1 and 3, in the step S2 of forming at least one engaging recess, at least one engaging recess 31 is formed in a sole portion or a back portion of the club head 30 by a machining method. The machining method may be milling, EDM (Electrical Discharge Machining) or engraving. Preferably, two engaging recesses 31 are formed in the sole portion of the club head 30 by milling.

With reference to FIGS. 1 and 3, in the step S3 of engaging the weight part into the engaging recess, at least one weight 40 is provided to engage the at least one engaging recess 31 of the club head 30.

The at least one weight part 40 may be made by casting or powder metallurgy and sintering process. The material for the at least one weight 40 may be selected from alloy materials such as WC(tungsten), WNi(tungsten nickel alloy) or WNiFe (tungsten-steel-nickel) or any metal material that has a specific gravity between 8.0 g.cc and 18 g.cc. The shape of the at least one weight 40 corresponds to that of the at least one engaging recess 31. Each one of the at least one weight part 40 has a channel 41 formed in a surface of the weight 40.

Preferably, two weights 40 are respectively mounted in two engaging recesses 31 and are made of WNi(tungsten nickel) alloy.

With reference to FIGS. 1 and 5, in the step S4 of integratedly connecting the weight with the club head by forging, the club head 30 with the weight parts 40 is heated to a pre-heating temperature of 700 to 1150 degrees Celsius. A fine forging die 20A is heated to a pre-heating temperature of 200 to 300 degrees Celsius. The club head 30 with the weight parts 40 is put into a cavity 21A of the fine forging die 20A and pressed by the fine forging die 20A. The pressure from the fine forging die 20A makes the material of the club head 30 flow to fill the cavity 21A. The weights 40 are completely covered by the flowing material of the club head 30 without any gap formed between the weight parts 40 and the club head 30. Additionally, after the cavity 21A has been filled, the remaining flowing material of the club head 30 becomes burrs and flows out from a parting line of the fine forging die 20A. Preferably, the volume of the burrs is 1 to 6 grams.

Furthermore, when the club head 30 is heated to a high temperature of 700 to 1150 degree (° C.) and under a high pressure during the forging process, nickel elements are separated out from the weight part 40 and are combined with the elements of the club head 30. This process generates a chemical reaction to strengthen the connection of the club head 30 and the weight parts 40.

With reference to FIG. 6, to form the final product of the club head 30 with the weight parts 40, the club head 30 and the weight parts 40 are integratedly connected. The differences of materials between the weight parts 40 and the club head 30 are visually distinguishable. Consequently, the manufacturing method in accordance with the present invention integratedly connects the club head 30 and the weight parts 40 to solve the problems such as easily falling down, shaking or generating sound of vibration in striking.

With reference to FIG. 7 in a second embodiment of the manufacturing method in accordance with the present invention, the elements and effects of the second embodiment are same as those of the first embodiment except that two engaging recesses 31 are formed in the back portion of the club head 30 by a machining method. The weights 40 are respectively mounted in the engaging recesses 31 in the back portion of the club head 30.

Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

What is claimed is:
 1. A manufacturing method comprising steps of: a club head forming step, comprising: providing a crude rod into a raw forging die, and forming the crude rod into a club head by a forging process; at least one engaging recess forming step, comprising: forming at least one engaging recess in a sole portion or a back portion of the club head by a machining method; at least one weight part engaging step, comprising: engaging at least one weight part into the at least one engaging recess of the club head; and a step of integratedly connecting the at least one weight part with the club head by forging, comprising: pre-heating the club head with the at least one weight part and placing the heated club head into a pre-heated fine forging die, and pressing the club head by a forging process to make the material of the club head flow and the at least one weight part completely covered by the material inside the club head.
 2. The manufacturing method as claimed in claim 1, wherein the club head with the at least one weight part is heated to a pre-heating temperature of 700 to 1150 degrees Celsius.
 3. The manufacturing method as claimed in claim 2, wherein the fine forging die is heated to a pre-heating temperature of 200 to 300 degrees Celsius.
 4. The manufacturing method as claimed in claim 3, wherein each one of the at least one weight part has a channel formed in a surface of the weight part.
 5. The manufacturing method as claimed in claim 1, wherein the at least one engaging recess is formed in the sole portion of the club head by milling.
 6. The manufacturing method as claimed in claim 2, wherein the at least one engaging recess is formed in the sole portion of the club head by milling.
 7. The manufacturing method as claimed in claim 3, wherein the at least one engaging recess is formed in the sole portion of the club head by milling.
 8. The manufacturing method as claimed in claim 4, wherein the at least one engaging recess is formed in the sole portion of the club head by milling.
 9. The manufacturing method as claimed in claim 1, wherein the at least one engaging recess is formed in the back portion of the club head by milling.
 10. The manufacturing method as claimed in claim 2, wherein the at least one engaging recess is formed in the back portion of the club head by milling.
 11. The manufacturing method as claimed in claim 3, wherein the at least one engaging recess is formed in the back portion of the club head by milling.
 12. The manufacturing method as claimed in claim 4, wherein the at least one engaging recess is formed in the back portion of the club head by milling.
 14. The manufacturing method as claimed in claim 3, wherein the forging process of forming the club head is a single forging step.
 15. The manufacturing method as claimed in claim 3, wherein the forging process of forming the club head is a multi-forging step.
 16. The manufacturing method as claimed in claim 14, wherein the at least one weight is made of WNi(tungsten nickel) alloy.
 17. The manufacturing method as claimed in claim 15, wherein the at least one weight is made of WNi(tungsten nickel) alloy. 